There are many types of surgical procedures where the surgeon must perform various operations on moving organs or tissue within the human body. For example, there has recently been an effort to perform coronary artery bypass surgery on a beating heart, without using cardiopulmonary bypass and a heart-lung machine. During a typical coronary bypass procedure, a bypass graft is used to help reestablish coronary artery circulation when a portion of the coronary artery is stenosed. Typically the graft vessel used in bypassing the stenosed portion of the coronary artery comprises one or more segments of the patient's saphenous vein or mammary artery.
Once the graft vessel is harvested and prepared, one end is sutured to the aorta, near its base, and the other end is attached to the coronary artery, just distal to the blockage. Some surgeons choose to complete all the proximal anastomoses, to the aorta, before commencing the distal anastomoses to the coronary arteries. In contrast, others choose to complete the distal anastomoses first. Regardless of the order, when undertaking the distal anastomoses to the coronary artery, it is important that the vessel graft be held steady and adjacent the coronary artery, with a minimum of vascular trauma and a minimum of visual and surgical obstruction by instruments in the narrow operative field.
The speed of performing such anastomoses can become extremely critical as well. Often the target vessel, usually the coronary artery, is occluded during the procedure so that the anastomoses can be performed more easily. It is very important to reconnect the supply of blood to the artery as soon as possible in order to minimize or prevent damage to the patient. Blood vessels are now normally anastomosed end-to-end or end-to-side by suturing techniques.
Conventionally, to suture two vessels together, a surgeon passes the pointed tip of a curved, surgical needle, having a suture attached to the blunt end, through the graft and target vessels. Then, the surgeon grasps the tip of the needle which has been penetrated through the tissues with a needle holder and pulls the needle through the tissues, wherein the suture follows the curved path of the needle. Usually separate sutures are applied first at the heel and toe locations of the openings being joined, and then the sutures are carefully pulled in order to draw together the vessels. Each suture is securely knotted when the openings are properly abutted at the heel and toes locations. Then a series of stitches are applied, one at time, between the heel and toe stitches. The stitches are applied using care to bring the vessels together intima-to-intima without dislodging any plaque which may be on the inside of the stenosed vessel.
Needless to say, the typical manual suturing technique, described above, can become very difficult when performed on a beating heart. A hand-sutured, anastomosis procedure on a non-beating heart generally takes the skilled surgeon from ten to twenty minutes to complete. Therefore, there have been some attempts to provide a device for immobilizing the portion of the heart near the anastomosis site, so that the surgeon can more readily complete the bypass procedure. In the past the surgeon would use a pair or forceps or a metal fork-type device to push against a portion of the heart to keep it still. Obviously, this could be a tiring task for the surgical assistant to hold the forceps in place while trying to stay out of the surgeon's way during the procedure.
Another type of stabilization device is called a "vacuum based" device. Vacuum based devices have members which grab onto a portion of the heart by suction and lift it up in order to immobilize it. An example of such a device is given in PCT International Publication Number WO 97/10753, published on Mar. 27, 1997 and which is hereby incorporated herein by reference. However, this device has many disadvantages, including a low integrity vacuum seal between the device and the heart caused by any number of reasons including particulates being trapped in the vacuum tube.